Fluid-pressure brake.



PATENTED OCT. 18, 1904.

OPPBRMANN.

FLUID PRESSURE BRAKE.

APPLICATION FILED DEC. 6, 1902.

N0 MODEL.

Atty.

' I improved brake apparatus by means of which UNITED STATES Patented October 18, 1904.

PATENT OFFIC GEORG OPPEEMANN, O'Pv HANOVER, GERMANY, ASSIGNOR TO THE WEST- INGHOUSE AIR BRAKE COMPANY, OF PITTsBURe, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

FLUID-PRESSURE BRAKE.

SPECIFICATION forming part of Letters Patent No. 772,903, dated October 18, 1904;.

Application filed December 6, 1902.

-To all whom, it may concern:

Be it known that I, GEORG OPPERMANN, a subject ofthe Emperor of Germany, residing in the city of Hanover, Germany, have invented a certain new and useful Improvement in Fluid-Pressure Brakes, of which improvement the following is a specification.

My invention relates to fluid pressure brakes, and has for its object to provide an a more perfect and complete control may be had of the pressure with which brakes are applied. I

With the present form of automatic air- I 5 brake as ordinarily used the brake-cylinder pressurecannot be accurately graduated during the release, thus rendering it more difficult to stop a train exactly upon a given spot without loss of time and making it almost impossible to control the train in descending heavy grades so as to keep a uniform speed. The object of my present invention is to overcome these difficulties, at the same time retaining all the advantages of the present automatic air-brake as well as other, advantages hereinafter set forth which are calculated to afford increased reliability of action under any condition of working and greater secur ity against failure of operation. Thisobject may be attained by the combination of any automatic brake apparatus with an equilib rium brake device having a piston normally subjected to equal pressures 'on its opposite sides and being applied by reducing the pressure upon one side, the same operating in conjunction with a pressure-reducing valve so as to charge the automatic brake apparatus with a higher degree of pressure than the equilibrium-brake, both brake devices being,

4 connected to the same main train-pipe.

In the accompanying drawing the figure shows one such form of combined fluid-pressure brake apparatus embodying my invention.

The main train-pipe 1 is provided with the usual branch pipe 2, connected to the triple serial No. 134,100- (No model.)

valve 3, auxiliary reservoir 4: and brake-cylinder 5, all of which comprise the ordinary automatic air-brake apparatus as applied to a car. In accordance with my improvement I provide an additional equilibrium brake device 6, the chamber 7 on one side of the piston 8 forming the reservoir, which may be of any desired shape or capacity, and the chamber 9 constituting the brake-cylinder, which is connected to the train-pipe 1 by means of branch pipe 10, containing the pressure-reducing valve 11.

. Any suitable form of connections. between 'the respective brake-pistons and brake-rigcylinder 9, acting on diaphragm 14, is suflicient to depress the same againt the adjustablespring15 and adapted to open freely for the passage of air from the cylinder 9 to the train-pipe 1 whenever the pressure in the train-pipe falls below that to which the pressure-reducing valve 11 is adjusted.

. The operation is as follows: Compressed air admitted from the main reservoir flows through the train-pipe l and through branch pipes 2 and 10 into the combined brake apparatus, charging the triple valve 3 and auXiliary reservoir 4, as well as both chambers 7 and 9 of the equilibrium brake device, with prevents it from flowing past the-piston in the opposite direction. When the pressure in the cylinder 9 and chamber 7 has reached the point at which the pressure-reducing valve 11 is set, this valve closes, thus shutting off further supply of air to the equilibrium-brake 6. The feed to the triple valve and auxiliary reservoir is not interrupted, however, and these parts will be charged up to full work ing train-pipe pressure. Upon a slight reduction of pressure being made in train-pipe 1 the triple valve operates in the usual way to admit air under pressure from the auxiliary reservoir 4: to the brake-cylinder 5, thus forcing the rod of piston 16 against the brakelever 12 and applying the brakes with moderate force. Each further reduction of train-pipe pressure Will cause the triple valve to again discharge air from reservoir 4 to brake-cylinder 5, and so increase the force with which the brakes are applied. The equilibrium-brake remains inactive until the train-pipe pressure has been reduced below the point to which the cylinder 9 is charged, as determined by the adjustment of the reducing-valve 11. Gempressed air then flows from cylinder 9 back through the red ucing-valve and branch pipe 10 to the train-pipe Land any further reduction in said train-pipe pressure is thereafter also producedin the cylinder 9. Since air cannot flow out from reservoir-chamber 7, an excess of pressure is maintained therein which now forces piston 8 into cylinder 9, thus exerting additional power upon the brake-lever 12 corresponding to the difference of the pressures in chambers 7 and 9. hen it is desired to release the brakes, the train-pipe pressure is increased and at first not being great enough to move the triple valve against the equalized auxiliary-reservoir pressure flows into the equilibrium-cylinder 9. The pressure in this cylinder then increases in the same proportion as the pressure is raised in the train-pipe, and the braking force exerted by piston 8 may therefore be reduced or increased at will by merely raising or lowering the train-pipe pressure. As soon as the train-pipe pressure is raised above the equalized pressure in the auxiliary reservoirs the triple valve is moved to release position and the pressure from brake-cylinder 5 is discharged to the atmosphere. The pressure-reducing valve 11 may be adjusted so as to charge the equilibriumbrake 6 With any desired pressure within certain limits, and this adjustment will determine the relative operation of the two brake-cylinders 5 and 9. If the valve 11 is adjusted to close at a train-pipe pressure sufliciently below normal, the automatic brake will be fully applied before the equilibrium-brake begins to act, and then upon increasing said train-pipe pressure the latter brake will be fully released before the release of the automatic brake. The reducing-valve may also be ad justed to start the action of the equilibriumbrake just When the full power is obtained in cylinder 5 and to effect the release of said cylinder at about the same mon'ientas the equilibrium brake has been fully released. In any case a sufiicient margin should be left between the commencement of the action of the two brakes to insure the quick action of the triple valve being promptly obtained before air can flow from equiliin-ium-cylinder 9 into the train-pipe.

It will now be evident from the foregoing description thatI have provided an improved combined brake apparatus including two brake devices, each being complete in itself, whereby if one should fail or become inoperative the other device may still be used, both brake devices being operated and controlled by a single line of train-pipe and adapted to apply the brakes with great force, which force may be gradually reduced or again increased as circumstances may require, thus securing perfect control for trains in descending heavy grades and also making stops at certain points easy.

Various changes and modifications in the general arrangement of parts may be made within the scope of my invention.

Having now described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. An automatic fluid-pressure brake device comprisinga train-pipe, triple valvc,auxiliary reservoir and brake-cylinder, in combination with an equilibrium brake-cylinder connected to the train-pipe and operated by variations of pressure therein.

2. In an automatic fluid-pressure brake apparatus, the combination with a train-pipe, triple valve, auxiliary reservoir and brakecylinder, of an equilibrium brake-cylimler connected to the train-pipe and a pressurereducing valve in said connection.

3. In a fluid-pressure brake apparatus, the combination with a train-pipe, auxiliary reservoir, triple valve and brake-cylinder, oi an additional brake-cylinder having a piston normally exposed to equal pressures on its opposite sides, and a connection for establishing communication between the train-pipeaml the additional brake-cylinder.

L In a fluid-pressure brake apparatus the combination with a train-pipe, auxiliary reservoir, triple valve and brake-cylimler, o 1' an additional brake-cylinder having a piston nor mally exposed to equal pressures on its oppo site sides, a passage leading from one side olsaid piston to the trainupe and a pressurereducing valve located in said passage.

5. In a fluid-pressure brake apparatus, the combination of an automatic brake device and an equilibrium brake device both connected to the same train-pipe.

6. In a fluid-pressure brake apparatus, the combination with a train-pipe, triple valve, auxiliary reservoir and brake-cylimler, ol an additional equilibrium brake cylinder and reservoir, a pipe or passage leading from the train-pipe to the latter brake-cylinder and means for feeding fluid under pressure from train-pipe to the reservoir of the equilibriumbrake.

,7. The combination of an'automatic airbrake device connected to a train-pipe, an equilibrlum brake device also connected to the same train-pipe and a pressure-reducing 4 valve located in send latter connection. IO

In testimony whereof I have hereunto set my hand.

GEORG OPPERMANN. v

Witnesses:

LEONORE RASCH, v i C. C. STEVENSON. 

